Hi Christoph,

On 07/14/2012 03:49 PM, Christoph Hellwig wrote:

Please send a version that does direct block I/O similar to xen-blkback
for now.

Seems xen-blkback converts the guest IO request to host bio and submit 
them directly. I was wondering whether this has a performance gain 
compared to AIO implementation.

If we get proper in-kernel aio support one day you can add
back file backend support.

I talked with Dave and Zack on the in-kernel aio patch which James 
pointed out:

http://marc.info/?l=linux-fsdevel&m=133312234313122

Dave will post a new version soon. I will wait for it.

-- 
Asias